I could use some advice from people experienced with bees. I have found a bumble bee nest in my front lawn on the edge of my 50' perennial border. I am a novice, but have identified these as the Golden Northern Bumble Bee. They seem to have built a nest in an old and quite large mouse/mole/vole nest. Should I try to get rid of the nest?

Background: I have two small children and a large dog that happily play in the front yard and can be pretty unaware. My husband mows the lawn every weekend. That's how we found the nest. The bees were pretty unhappy that he mowed over their home, several came at him, and he was stung by one. He is not allergic, but out children suffer from allergies. (I don't know how allergic the children are to bee stings, they have never been stung.) That being said, the bees seem very non-aggressive. You can stand right next to the nest and watch the bees for hours. Since we found the bee nest, my husband has mowed around it and clipped the grass around the nest by hand and has not been attacked or bothered at all by the bees. You can see these bees happily pollinating the perennials - black-eyed susans, purple and white confelowers, liatris, etc. There is lots of food for them. We have used organic gardening practices for the past 9 years, which has led to a beautiful garden full of birds and insect life. I'm so pleased because in the early evening, we look like a fireworks display when all the lightning bugs come out of the lawn and start blinking around. It is a beautiful sight.

Anyhow, what I am mostly worried about it what happens next. Do these bees get more aggressive as the summer progresses? Will I have more nests in troublesome locations next year? Or do the new queens move FAR away before they build their own nest? Will the current nest get enormous and more difficult to eradicate if we need to treat it later? Right now, I am considering keeping the kids away from the nest by putting a low border fence (1 ft) around it. This will do little to deter the happy-go-lucky standard poodle who bounds through and over everything. I appreciate any advice you can provide.